Hey John! I wanted to ask your opinion--I am working on trying to get into my cargo boxes. I have all but one of them open-the one that was too rusty. I ground off the rivets and pulled the handle assembly out. I cut it loose from the cable that goes to the latches on the sides. One of the latches opens fine, but the other one is rusted in place. I had this same problem in one of the other boxes, but it was one of the boxes that's divided in half, and I was able to crawl inside and unscrew the latch. When I looked at the latch, there was so much rust built up on the "bolt" part of the latch that it couldn't slide in the "housing channel" part of the latch.
This box is a single large box, and there's no way I can access the back of the latch. I'm REALLY loathe to destroy the door, but I'm not sure there's any other way to get the box open.